"Over_used/Over_spent"(Losses) and "Under_used/Under_spent"(Savings) _ on a monthly basis based on data entered, the program also automatically plotted charts showing trends over a 12 month period.
Custom spreadsheet solutions which survive long after the developer has "left the scene", are often those which users accept because they discover it _ among other benefits _ makes their work quicker and easier to do. That is why the best person to develop such solutions tend to be one who works in that area, and is therefore familiar with the way the manual system operates. S/he would have an "insider's" perspective of the best way to introduce automation other users will readily adopt _ even as it solves the identified problem(s).
1. The Pareto Principle _ Using spreadsheet tracking, you can easily apply the Pareto principle in deciding which of your income sources and expense channels(i.e. products and services sales) to focus on in order to maximize profits. Considering that you are most likely to use the same marketing/sales resources to serve your customers, it only follows that if you focus on your biggest margin selling products/services, you will get increased profits at more or less the same cost.
The savings _ from using your "in house" expertise _ in terms of money and man_hours alone, will quickly justify the investment you make in "developing the needed skills" _ especially, when you compare what you spend with the cost of purchasing a commercial software application _ or even engaging the services of an Excel VB developer.